User`s guide

Targ et Preferences
No deadlock condition can occur because there is no wait
state. Data transmission is asynchronous. W ith this mode,
it is possible the receiving side could miss data, b ut if the
data is noncritical, using raw data mode can avoid blocking
any processes.
When you select protocol mode, some handshaking between
host and processor occurs. The transmitting side sends
$SND to indicate it is ready to transmit. The receiving
side sends back $RDY to indicate it is ready to receive.
Thetransmittingsidethensendsdataand,whenthe
transmission is completed, it sends a checksum.
Advantages to using protocol m ode include:
• Avoids deadlock
• Ensures that data is received correctly (checksum)
• Ensures that data is actually received by processor
• Ensures time consistency; each side waits for its turn to
send or receive
Note Deadlocks can occur i f one SC I Transmit block tries
to communicate with more than one SCI Receive block on
different COM po rts when both are blocking (using protocol
mode). Deadlocks cannot occur on the same COM port.
Data byte order
Select
Little Endian or Big Endian.
Data swap width
Select
8-bits or 16-bits.
Enable Loopback
Select this parameter to enable the loopback function for
self-test and diagnostic purposes only. When this function
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